Metal-turning lathe



(No Model.)

I. E. REED & J. R. BACK.

METAL TURNING LATHE.

No. 332,888. Patented Dec. 22, 1885.

UNrrEn STATES PATENT Carton.

FREDERICK E. REED AND JOHN R. BACK, OF WORCESTER, MASSACHUSETTS.

METAL-TURNING LATHE.

SPECIFICATION forming part of Letters Patent No. 332,833, dated December22, 1885.

Application filed October 14, 1885.

To all whom it may concern:

Be it known that we, FEEDEEIoK E. REED and JOHN R. BACK, citizens of theUnited States, residing at Worcester, in the county of Worcester andState of Massachusetts, haveinvented certain new and useful Improvementsin Metal-Turning Lathes, of which the following is a specification,containing a full, clear, and exact description of the'same, referencebeing had to the accompanying drawings, in Which- Figure 1 represents afront elevation of a metal-turning lathe embodying our invention. Fig. 2is an end view with the heads removed. Figs. 3 and 4 are end views ofthe bed, showing modified forms of the device illustrated by Fig. 2; andFig. 5 is a front view of the bed with the gears connecting the screwand feedrod placed inside their bearings instead of at the end, as shownin Fig. 1.

Similar parts are indicated by similar letters in the several views.

Our invention relates to that part of metalturning lathes known as thefeeding mechanism; and it consists in means for actuating the feed-roddirectly from the leadingscrew when both are held in bearings fixed tothe bed of the lathe, whereby we are enabled to obtain a greater rangein the variation of the feed than is possible by the methods now in use.

A A denotes the bed of the lathe, carrying the usual head-stocks and thesliding t0ol-rest B, having a traversing motion along the bed. Journaled in bearings a a on the bed is a screwthreaded shaft,technically known as a leading-screw, and rotated by a system ofgearing, a, connecting the screw with the shaft D, which is driven bythe gear b on the spindle E. By changing the sizes of the driving-gearon shaft D and the driven gear on the screw 0 the speed of a theleading-screw may be varied relatively to the speed of the spindle E,which is also the speed of the work. A claspnut attached to the slidingtool-restB beneath the apron F, and not shown in the drawings, is madeto engage the leading-screw C and impart a traversing motion to thetool-rest B along the bed of the lathe, causing the tool to form anaccurate screw-thread upon the work. Upon the shaft D are placed thestep-pulleys d,

which communicate motion by a belt-connec- Serial No. 179,881. (Nomodel.)

tion to the step-pulley e on the feed-rod C. By means of a slot andspline (not shown) the rod G is made to impart motion to a train ofgearing turning on studs attached to the apron F, which gearing, actingupon the rack H, fixed to the bed of the lathe, causes a traversingmotion of the tool-rest along the bed of the lathe. The leading-screwand feed-rod may be connected or disconnected at will from the tool-restand also from the rotating shaft D.

The construction and operation of so much of the metal-turning lathe ashas already been described is common and well known, and has thereforenot been shown in full in the drawings or described in detail in thespecification. A great variation in the speed of the leadingscrew C issecured by increasing the number of sizes of change-gears, while thespeed of the feed-rod G is limited to the changes which can be effectedby the steps of the pulleys d and e.

To secure a greater variation in the speed of the feed-rod is the objectof our invention; and it consists in attaching a driving-pinion, f, tothe end of the leading-screw, which, through an intermediate gear, h,turning in a stud, g, in the bed, drives a gear, 9, attached to thefeed-rod G. The stud g is long enough to allow the intermediate gear, h,to be drawn out of contact with the gears f and 9, allowing thefeed-shaft to be driven by a belt on the pulley d, and in the usualmanner, if desired.

We use a gear, f, on the screw C, smaller than the gear 9 on thefeed-rod G, for the purpose of magnifying the variations of speedeffected by the several changes of the gears c.

Lathes are sometimes constructed with the leading-screw upon the backside of the bed and the feeding-rod upon the front side, as shown inFigs. 3and 4. In such cases we communicate motion to the feed-shaft, asshown in Fig. 3, by an intermediate gear, h, or, as shown in Fig. 4, bya belt-connection, both methods coming within the scope of our presentinvention.

We do not confine ourselves to the use of the gears f and g at the endof the screw C and feed-rod G, as they may be placed inside the bearingsof the screw and feed-rod, as shown in Fig. 5, if brought beyond thetraverse of the apron F.

We are aware that lathes have been constructed in which theleading-screw has been made to perform the function of a feed-rod byhaving a slot itsentire length and a gear connected with the screw by aspline. YVe are also aware that the leading-screw has been driven fromthe feed-rod, which has been connected by changegears with the shaft D;also, that a short shaft carried in bearings attached to the apron F hasbeen driven by a geareonnection with the leading-screw. \Ve claim noneof these construct-ions; but

What We do claim, and desire to secure by Letters Patent, is

1. The combination, with the tool-rest of a metal-turning" lathe, of aleading-screw connected with the rotating spindle and held in

